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          <a name="Performance Benchmarks"><strong>Performance Benchmarks</strong></a>
        </font>
      </td></tr>
      <tr><td>
        <blockquote>
                                    <p>
                The purpose of these user-submitted performance figures is to
                give current and potential users of Lucene a sense
                of how well Lucene scales. If the requirements for an upcoming
                project is similar to an existing benchmark, you
                will also have something to work with when designing the system
                architecture for the application.
            </p>
                                                <p>
                If you've conducted performance tests with Lucene, we'd
                appreciate if you can submit these figures for display
                on this page. Post these figures to the lucene-user mailing list
                using this
                <a href="benchmarktemplate.xml">template</a>.
            </p>
                            </blockquote>
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        <font color="#ffffff" face="arial,helvetica,sanserif">
          <a name="Benchmark Variables"><strong>Benchmark Variables</strong></a>
        </font>
      </td></tr>
      <tr><td>
        <blockquote>
                                    <p>
                <ul>
                    <p>
                        <b>Hardware Environment</b><br />
                        <li><i>Dedicated machine for indexing</i>: Self-explanatory
                            (yes/no)</li>
                        <li><i>CPU</i>: Self-explanatory (Type, Speed and Quantity)</li>
                        <li><i>RAM</i>: Self-explanatory</li>
                        <li><i>Drive configuration</i>: Self-explanatory (IDE, SCSI,
                            RAID-1, RAID-5)</li>
                    </p>
                    <p>
                        <b>Software environment</b><br />
                        <li><i>Java Version</i>: Version of Java SDK/JRE that is run
                        </li>
                        <li><i>Java VM</i>: Server/client VM, Sun VM/JRockIt</li>
                        <li><i>OS Version</i>: Self-explanatory</li>
                        <li><i>Location of index</i>: Is the index stored in filesystem
                            or database? Is it on the same server(local) or
                            over the network?</li>
                    </p>
                    <p>
                        <b>Lucene indexing variables</b><br />
                        <li><i>Number of source documents</i>: Number of documents being
                            indexed</li>
                        <li><i>Total filesize of source documents</i>:
                            Self-explanatory</li>
                        <li><i>Average filesize of source documents</i>:
                            Self-explanatory</li>
                        <li><i>Source documents storage location</i>: Where are the
                            documents being indexed located?
                            Filesystem, DB, http,etc</li>
                        <li><i>File type of source documents</i>: Types of files being
                            indexed, e.g. HTML files, XML files, PDF files, etc.</li>
                        <li><i>Parser(s) used, if any</i>: Parsers used for parsing the
                            various files for indexing,
                            e.g. XML parser, HTML parser, etc.</li>
                        <li><i>Analyzer(s) used</i>: Type of Lucene analyzer used</li>
                        <li><i>Number of fields per document</i>: Number of Fields each
                            Document contains</li>
                        <li><i>Type of fields</i>: Type of each field</li>
                        <li><i>Index persistence</i>: Where the index is stored, e.g.
                            FSDirectory, SqlDirectory, etc</li>
                    </p>
                    <p>
                        <b>Figures</b><br />
                        <li><i>Time taken (in ms/s as an average of at least 3 indexing
                                runs)</i>: Time taken to index all files</li>
                        <li><i>Time taken / 1000 docs indexed</i>: Time taken to index
                            1000 files</li>
                        <li><i>Memory consumption</i>: Self-explanatory</li>
                    </p>
                    <p>
                        <b>Notes</b><br />
                        <li><i>Notes</i>: Any comments which don't belong in the above,
                            special tuning/strategies, etc</li>
                    </p>
                </ul>
            </p>
                            </blockquote>
        </p>
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        <font color="#ffffff" face="arial,helvetica,sanserif">
          <a name="User-submitted Benchmarks"><strong>User-submitted Benchmarks</strong></a>
        </font>
      </td></tr>
      <tr><td>
        <blockquote>
                                    <p>
                These benchmarks have been kindly submitted by Lucene users for
                reference purposes.
            </p>
                                                <p><b>We make NO guarantees regarding their accuracy or
                    validity.</b>
            </p>
                                                <p>We strongly recommend you conduct your own
                performance benchmarks before deciding on a particular
                hardware/software setup (and hopefully submit
                these figures to us).
            </p>
                                                    <table border="0" cellspacing="0" cellpadding="2" width="100%">
      <tr><td bgcolor="#828DA6">
        <font color="#ffffff" face="arial,helvetica,sanserif">
          <a name="Hamish Carpenter's benchmarks"><strong>Hamish Carpenter's benchmarks</strong></a>
        </font>
      </td></tr>
      <tr><td>
        <blockquote>
                                    <ul>
                    <p>
                        <b>Hardware Environment</b><br />
                        <li><i>Dedicated machine for indexing</i>: yes</li>
                        <li><i>CPU</i>: Intel x86 P4 1.5Ghz</li>
                        <li><i>RAM</i>: 512 DDR</li>
                        <li><i>Drive configuration</i>: IDE 7200rpm Raid-1</li>
                    </p>
                    <p>
                        <b>Software environment</b><br />
                        <li><i>Java Version</i>: 1.3.1 IBM JITC Enabled</li>
                        <li><i>Java VM</i>: </li>
                        <li><i>OS Version</i>: Debian Linux 2.4.18-686</li>
                        <li><i>Location of index</i>: local</li>
                    </p>
                    <p>
                        <b>Lucene indexing variables</b><br />
                        <li><i>Number of source documents</i>: Random generator. Set
                            to make 1M documents
                            in 2x500,000 batches.</li>
                        <li><i>Total filesize of source documents</i>: &gt; 1GB if
                            stored</li>
                        <li><i>Average filesize of source documents</i>: 1KB</li>
                        <li><i>Source documents storage location</i>: Filesystem</li>
                        <li><i>File type of source documents</i>: Generated</li>
                        <li><i>Parser(s) used, if any</i>: </li>
                        <li><i>Analyzer(s) used</i>: Default</li>
                        <li><i>Number of fields per document</i>: 11</li>
                        <li><i>Type of fields</i>: 1 date, 1 id, 9 text</li>
                        <li><i>Index persistence</i>: FSDirectory</li>
                    </p>
                    <p>
                        <b>Figures</b><br />
                        <li><i>Time taken (in ms/s as an average of at least 3
                                indexing runs)</i>: </li>
                        <li><i>Time taken / 1000 docs indexed</i>: 49 seconds</li>
                        <li><i>Memory consumption</i>:</li>
                    </p>
                    <p>
                        <b>Notes</b><br />
                            <p>
                                A windows client ran a random document generator which
                                created
                                documents based on some arrays of values and an excerpt
                                (approx 1kb)
                                from a text file of the bible (King James version).<br />
                                These were submitted via a socket connection (open throughout
                                indexing process).<br />
                                The index writer was not closed between index calls.<br />
                                This created a 400Mb index in 23 files (after
                                optimization).<br />
                            </p>
                            <p>
                                <u>Query details</u>:<br />
                            </p>
                            <p>
                                Set up a threaded class to start x number of simultaneous
                                threads to
                                search the above created index.
                            </p>
                            <p>
                                Query:  +Domain:sos +(+((Name:goo*^2.0 Name:plan*^2.0)
                                (Teaser:goo* Tea
                                ser:plan*) (Details:goo* Details:plan*)) -Cancel:y)
                                +DisplayStartDate:[mkwsw2jk0
                                -mq3dj1uq0] +EndDate:[mq3dj1uq0-ntlxuggw0]
                            </p>
                            <p>
                                This query counted 34000 documents and I limited the returned
                                documents
                                to 5.
                            </p>
                            <p>
                                This is using Peter Halacsy's IndexSearcherCache slightly
                                modified to
                                be a singleton returned cached searchers for a given
                                directory. This
                                solved an initial problem with too many files open and
                                running out of
                                linux handles for them.
                            </p>
                            <pre>
                                Threads|Avg Time per query (ms)
                                1       1009ms
                                2       2043ms
                                3       3087ms
                                4       4045ms
                                ..        .
                                ..        .
                                10      10091ms
                            </pre>
                            <p>
                                I removed the two date range terms from the query and it made
                                a HUGE
                                difference in performance. With 4 threads the avg time
                                dropped to 900ms!
                            </p>
                            <p>Other query optimizations made little difference.</p>
                    </p>
                </ul>
                                                <p>
                    Hamish can be contacted at hamish at catalyst.net.nz.
                </p>
                            </blockquote>
      </td></tr>
      <tr><td><br/></td></tr>
    </table>
                                                    <table border="0" cellspacing="0" cellpadding="2" width="100%">
      <tr><td bgcolor="#828DA6">
        <font color="#ffffff" face="arial,helvetica,sanserif">
          <a name="Justin Greene's benchmarks"><strong>Justin Greene's benchmarks</strong></a>
        </font>
      </td></tr>
      <tr><td>
        <blockquote>
                                    <ul>
                    <p>
                        <b>Hardware Environment</b><br />
                        <li><i>Dedicated machine for indexing</i>: No, but nominal
                            usage at time of indexing.</li>
                        <li><i>CPU</i>: Compaq Proliant 1850R/600 2 X pIII 600</li>
                        <li><i>RAM</i>: 1GB, 256MB allocated to JVM.</li>
                        <li><i>Drive configuration</i>: RAID 5 on Fibre Channel
                            Array</li>
                    </p>
                    <p>
                        <b>Software environment</b><br />
                        <li><i>Java Version</i>: 1.3.1_06</li>
                        <li><i>Java VM</i>: </li>
                        <li><i>OS Version</i>: Winnt 4/Sp6</li>
                        <li><i>Location of index</i>: local</li>
                    </p>
                    <p>
                        <b>Lucene indexing variables</b><br />
                        <li><i>Number of source documents</i>: about 60K</li>
                        <li><i>Total filesize of source documents</i>: 6.5GB</li>
                        <li><i>Average filesize of source documents</i>: 100K
                            (6.5GB/60K documents)</li>
                        <li><i>Source documents storage location</i>: filesystem on
                            NTFS</li>
                        <li><i>File type of source documents</i>: </li>
                        <li><i>Parser(s) used, if any</i>: Currently the only parser
                            used is the Quiotix html
                            parser.</li>
                        <li><i>Analyzer(s) used</i>: SimpleAnalyzer</li>
                        <li><i>Number of fields per document</i>: 8</li>
                        <li><i>Type of fields</i>: All strings, and all are stored
                            and indexed.</li>
                        <li><i>Index persistence</i>: FSDirectory</li>
                    </p>
                    <p>
                        <b>Figures</b><br />
                        <li><i>Time taken (in ms/s as an average of at least 3
                                indexing runs)</i>: 1 hour 12 minutes, 1 hour 14 minutes and 1 hour 17
                            minutes.  Note that the #
                            and size of documents changes daily.</li>
                        <li><i>Time taken / 1000 docs indexed</i>: </li>
                        <li><i>Memory consumption</i>: JVM is given 256MB and uses it
                            all.</li>
                    </p>
                    <p>
                        <b>Notes</b><br />
                            <p>
                                We have 10 threads reading files from the filesystem and
                                parsing and
                                analyzing them and the pushing them onto a queue and a single
                                thread poping
                                them from the queue and indexing.  Note that we are indexing
                                email messages
                                and are storing the entire plaintext in of the message in the
                                index.  If the
                                message contains attachment and we do not have a filter for
                                the attachment
                                (ie. we do not do PDFs yet), we discard the data.
                            </p>
                    </p>
                </ul>
                                                <p>
                    Justin can be contacted at tvxh-lw4x at spamex.com.
                </p>
                            </blockquote>
      </td></tr>
      <tr><td><br/></td></tr>
    </table>
                                                    <table border="0" cellspacing="0" cellpadding="2" width="100%">
      <tr><td bgcolor="#828DA6">
        <font color="#ffffff" face="arial,helvetica,sanserif">
          <a name="Daniel Armbrust's benchmarks"><strong>Daniel Armbrust's benchmarks</strong></a>
        </font>
      </td></tr>
      <tr><td>
        <blockquote>
                                    <p>
                    My disclaimer is that this is a very poor "Benchmark".  It was not done for raw speed,
                    nor was the total index built in one shot.  The index was created on several different
                    machines (all with these specs, or very similar), with each machine indexing batches of 500,000 to
                    1 million documents per batch.  Each of these small indexes was then moved to a
                    much larger drive, where they were all merged together into a big index.
                    This process was done manually, over the course of several months, as the sources became available.
                </p>
                                                <ul>
                    <p>
                        <b>Hardware Environment</b><br />
                        <li><i>Dedicated machine for indexing</i>: no - The machine had moderate to low load.  However, the indexing process was built single
                            threaded, so it only took advantage of 1 of the processors.  It usually got 100% of this processor.</li>
                        <li><i>CPU</i>: Sun Ultra 80 4 x 64 bit processors</li>
                        <li><i>RAM</i>: 4 GB Memory</li>
                        <li><i>Drive configuration</i>: Ultra-SCSI Wide 10000 RPM 36GB Drive</li>
                    </p>
                    <p>
                        <b>Software environment</b><br />
                        <li><i>Java Version</i>: 1.3.1</li>
                        <li><i>Java VM</i>: </li>
                        <li><i>OS Version</i>: Sun 5.8 (64 bit)</li>
                        <li><i>Location of index</i>: local</li>
                    </p>
                    <p>
                        <b>Lucene indexing variables</b><br />
                        <li><i>Number of source documents</i>: 13,820,517</li>
                        <li><i>Total filesize of source documents</i>: 87.3 GB</li>
                        <li><i>Average filesize of source documents</i>: 6.3 KB</li>
                        <li><i>Source documents storage location</i>: Filesystem</li>
                        <li><i>File type of source documents</i>: XML</li>
                        <li><i>Parser(s) used, if any</i>: </li>
                        <li><i>Analyzer(s) used</i>: A home grown analyzer that simply removes stopwords.</li>
                        <li><i>Number of fields per document</i>: 1 - 31</li>
                        <li><i>Type of fields</i>: All text, though 2 of them are dates (20001205) that we filter on</li>
                        <li><i>Index persistence</i>: FSDirectory</li>
                        <li><i>Index size</i>: 12.5 GB</li>
                    </p>
                    <p>
                        <b>Figures</b><br />
                        <li><i>Time taken (in ms/s as an average of at least 3
                                indexing runs)</i>: For 617271 documents, 209698 seconds (or ~2.5 days)</li>
                        <li><i>Time taken / 1000 docs indexed</i>: 340 Seconds</li>
                        <li><i>Memory consumption</i>: (java executed with) java -Xmx1000m -Xss8192k so
                            1 GB of memory was allotted to the indexer</li>
                    </p>
                    <p>
                        <b>Notes</b><br />
                            <p>
                                The source documents were XML.  The "indexer" opened each document one at a time, ran an
                                XSL transformation on them, and then proceeded to index the stream.  The indexer optimized
                                the index every 50,000 documents (on this run) though previously, we optimized every
                                300,000 documents.  The performance didn't change much either way.  We did no other
                                tuning (RAM Directories, separate process to pretransform the source material, etc)
                                to make it index faster.  When all of these individual indexes were built, they were
                                merged together into the main index.  That process usually took ~ a day.
                            </p>
                    </p>
                </ul>
                                                <p>
                    Daniel can be contacted at Armbrust.Daniel at mayo.edu.
                </p>
                            </blockquote>
      </td></tr>
      <tr><td><br/></td></tr>
    </table>
                                                    <table border="0" cellspacing="0" cellpadding="2" width="100%">
      <tr><td bgcolor="#828DA6">
        <font color="#ffffff" face="arial,helvetica,sanserif">
          <a name="Geoffrey Peddle's benchmarks"><strong>Geoffrey Peddle's benchmarks</strong></a>
        </font>
      </td></tr>
      <tr><td>
        <blockquote>
                                    <p>
                  I'm doing a technical evaluation of search engines 
                  for Ariba, an enterprise application software company.
                   I compared Lucene to a commercial C language based
                  search engine which I'll refer to as vendor A.  
                  Overall Lucene's performance was similar to vendor A
                  and met our application's requirements.  I've
                  summarized our results below.
                </p>
                                                <p>
                  Search scalability:<br />
                  We ran a set of 16 queries in a single thread for 20
                  iterations.  We report below the times for the last 15
                  iterations (ie after the system was warmed up).   The
                  4 sets of results below are for indexes with between
                  50,000 documents to 600,000 documents.  Although the
                  times for Lucene grew faster with document count than
                  vendor A they were comparable.
                </p>
                                                <pre>
50K  documents
Lucene   5.2   seconds
A        7.2
200K
Lucene   15.3
A        15.2
400K
Lucene    28.2
A         25.5
600K
Lucene    41
A         33
</pre>
                                                <p>
                  Individual Query times:<br />
                  Total query times are very similar between the 2
                  systems but there were larger differences when you
                  looked at individual queries.
                </p>
                                                <p>
                  For simple queries with small result sets Vendor A was
                  consistently faster than Lucene.   For example a
                  single query might take vendor A 32 thousands of a
                  second and Lucene 64 thousands of a second.    Both
                  times are however well within acceptable response
                  times for our application.
                </p>
                                                <p>
                  For simple queries with large result sets Vendor A was
                  consistently slower than Lucene.   For example a
                  single query might take vendor A 300 thousands of a
                  second and Lucene 200 thousands of a second.
                  For more complex queries of the form   (term1 or term2
                  or term3)  AND (term4 or term5 or term6) AND (term7 or
                  term8)    the results were more divergent.  For
                  queries with small result sets Vendor A generally had
                  very short response times and sometimes Lucene had
                  significantly larger response times.  For example
                  Vendor A might take 16 thousands of a second and
                  Lucene might take 156.   I do not consider it to be
                  the case that Lucene's response time grew unexpectedly
                  but rather that Vendor A appeared to be taking
                  advantage of an optimization which Lucene didn't have.
                    (I believe there's been discussions on the dev
                  mailing list on complex queries of this sort.)
                </p>
                                                <p>
                  Index Size:<br />
                  For our test data the size of both indexes grew
                  linearly with the number of documents.   Note that
                  these sizes are compact sizes, not maximum size during
                  index loading.   The numbers below are from running du
                  -k in the directory containing the index data.   The
                  larger number's below for Vendor A may be because it
                  supports additional functionality not available in
                  Lucene.   I think it's the constant rate of growth
                  rather than the absolute amount which is more
                  important.
                </p>
                                                <pre>
50K  documents
Lucene      45516 K
A           63921
200K
Lucene      171565
A           228370
400K
Lucene      345717
A           457843
600K
Lucene      511338
A           684913
</pre>
                                                <p>
                  Indexing Times:<br />
                  These times are for reading the documents from our
                  database, processing them, inserting them into the
                  document search product and index compacting.   Our
                  data has a large number of fields/attributes.   For
                  this test I restricted Lucene to 24 attributes to
                  reduce the number of files created.  Doing this I was
                  able to specify a merge width for Lucene of 60.   I
                  found in general that Lucene indexing performance to
                  be very sensitive to changes in the merge width.  
                  Note also that our application does a full compaction
                  after inserting every 20,000 documents.   These times
                  are just within our acceptable limits but we are
                  interested in alternatives to increase Lucene's
                  performance in this area.
                </p>
                                                <p>
<pre>
600K documents
Lucene       81 minutes
A            34 minutes
</pre>
</p>
                                                <p>
                  (I don't have accurate results for all sizes on this
                  measure but believe that the indexing time for both
                  solutions grew essentially linearly with size.   The
                  time to compact the index generally grew with index
                  size but it's a small percent of overall time at these
                  sizes.)
                </p>
                                                <ul>
                    <p>
                        <b>Hardware Environment</b><br />
                        <li><i>Dedicated machine for indexing</i>: yes</li>
                        <li><i>CPU</i>: Dell Pentium 4 CPU 2.00Ghz, 1cpu</li>
                        <li><i>RAM</i>: 1 GB Memory</li>
                        <li><i>Drive configuration</i>: Fujitsu MAM3367MP SCSI </li>
                    </p>
                    <p>
                        <b>Software environment</b><br />
                        <li><i>Java Version</i>: 1.4.2_02</li>
                        <li><i>Java VM</i>: JDK</li>
                        <li><i>OS Version</i>: Windows XP </li>
                        <li><i>Location of index</i>: local</li>
                    </p>
                    <p>
                        <b>Lucene indexing variables</b><br />
                        <li><i>Number of source documents</i>: 600,000</li>
                        <li><i>Total filesize of source documents</i>: from database</li>
                        <li><i>Average filesize of source documents</i>: from database</li>
                        <li><i>Source documents storage location</i>: from database</li>
                        <li><i>File type of source documents</i>: XML</li>
                        <li><i>Parser(s) used, if any</i>: </li>
                        <li><i>Analyzer(s) used</i>: small variation on WhitespaceAnalyzer</li>
                        <li><i>Number of fields per document</i>: 24</li>
                        <li><i>Type of fields</i>: A1 keyword, 1 big unindexed, rest are unstored and a mix of tokenized/untokenized</li>
                        <li><i>Index persistence</i>: FSDirectory</li>
                        <li><i>Index size</i>: 12.5 GB</li>
                    </p>
                    <p>
                        <b>Figures</b><br />
                        <li><i>Time taken (in ms/s as an average of at least 3
                                indexing runs)</i>: 600,000 documents in 81 minutes   (du -k = 511338)</li>
                        <li><i>Time taken / 1000 docs indexed</i>: 123 documents/second</li>
                        <li><i>Memory consumption</i>: -ms256m -mx512m -Xss4m -XX:MaxPermSize=512M</li>
                    </p>
                    <p>
                        <b>Notes</b><br />
                          <p>
                            <li>merge width of 60</li>
                            <li>did a compact every 20,000 documents</li>
                          </p>
                    </p>
                </ul>
                            </blockquote>
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